`CuSO_(4).5H_(2)O` is blue in colour where as anhydrous `CuSO_(4)` is colourless. Why?

Aqueous Cu^(2+) ions are blue in colour, where as Aqueous Zn^(2+) ions are colourless. Why ?

CuSO_(4). 5H_(2)O has pale blue colour while ZnSO_(4), 7h_(2)O is white. Discuss.

CuSO_(4) +NH_(4)OH gives deep blue complex of

CaCl is colourless, while CuSO_(4).5H_(2)O is coloured. Explain?

Eventhough Cu^(2+) has one unpaired d - electron, anhydrous copper sulphate is colourless. Why?

CuSO_4 is more soluble in ammonia. Why ?

A solution of [Ni(H_(2)O)_(6)]^(2+) is green but a solution of [Ni(CN)_(4)]^(2-) is colourless. Why?

A metal sulphide (A) gives (B) gas with rotten egg and (C) a colourless sulphates, when treated with dil. H_(2)SO_(4) (B) reacts with K_(2)Cr_(2)O_(7)//H^(+) to form (D) a white grey element. (D) burns in oxygen to yield (E) a colourless gas. If (B) is added in (E), it gives (D) and colourless liquid, which turns anhydrous CuSO_(4) blue. (C) gives a precipitate with NH_(3(aq)) or NaOH which dissolves in excess of NaOH. B is

A metal sulphide (A) gives (B) gas with rotten egg and (C) a colourless sulphates, when treated with dil. H_(2)SO_(4) (B) reacts with K_(2)Cr_(2)O_(7)//H^(+) to form (D) a white grey element. (D) burns in oxygen to yield (E) a colourless gas. If (B) is added in (E), it gives (D) and colourless liquid, which turns anhydrous CuSO_(4) blue. (C) gives a precipitate with NH_(3(aq)) or NaOH which dissolves in excess of NaOH. C is

A metal sulphide (A) gives (B) gas with rotten egg and (C) a colourless sulphates, when treated with dil. H_(2)SO_(4) (B) reacts with K_(2)Cr_(2)O_(7)//H^(+) to form (D) a white grey element. (D) burns in oxygen to yield (E) a colourless gas. If (B) is added in (E), it gives (D) and colourless liquid, which turns anhydrous CuSO_(4) blue. (C) gives a precipitate with NH_(3(aq)) or NaOH which dissolves in excess of NaOH. E is